Use of alkylpolyxylosides in cosmetics

ABSTRACT

A composition, method of preparation 1  and use to enhance the cosmetic feel of oil-in-water emulsions based upon the addition to the oil in water emulsion of one or more alkylpolyxylosides represented by formula:
 
R—O—(X) p ,
         wherein p is a decimal number between 1 and 5,   wherein X is a xylose residue, and   wherein R is a branched alkyl radical represented by the formula:
 
CH(C n H 2n+1 )(C m H 2m+1 )—CH 2 —
   wherein m is an integer between 6 and 12, n is an integer between 8 and 16, and the sum of m+n is in the range of from about 14 to 26.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject of the present invention is the use of particularalkylpolyxylosides as agents enhancing the cosmetic feel of oil-in-wateremulsions containing a polymer, and the oil-in-water emulsionscontaining such alkylpolyxylosides.

2. Related Art

Cosmetic emulsions with an aqueous continuous phase (that is to say ofthe oil-in-water or O/W type) increasingly frequently contain polymerswhich are used as thickeners, emulsifiers or stabilizers. The use ofthese polymers make it possible to reduce or eliminate the quantity oftraditional emulsifiers. However, the feel of the cosmetic compositionsthus obtained loses in richness and becomes aqueous.

Patent application FR 00 04414, filed on 6 Apr. 2000, describescompounds of formula:R—O—(X)_(p)in which:

-   p represents a decimal number between 1 and 5,-   X represents a xylose residue, and-   R represents a branched alkyl radical of formula:    CH(C_(n)H_(2n+1))(C_(m)H_(2m+1))—CH₂—    in which m is an integer between 6 and 18, n is an integer between 4    and 18 and the sum n+m is greater than or equal to 10.

These compounds are recommended as surfactants.

It has now been discovered that alkylpolyxylosides obtained from aGuerbet alcohol having from 16 to 28 carbon atoms make it possible toenhance the feel of oil-in-water emulsions containing a polymer.

SUMMARY OF THE INVENTION

The invention provides a composition, as well as a method ofpreparation, comprising at least one alkylpolyxyloside represented byformula (I);R—O—(X)_(p)  (I),

wherein p is a decimal number between 1 and 5,

wherein X is a xylose residue, and

wherein R is a branched alkyl radical represented by the formula:CH(C_(n)H_(2n+1))(C_(m)H_(2m+i))—CH₂—

wherein m is an integer between 6 and 12, n is an integer between 8 and16, and the sum of m+n is in the range of from 14 to 26. The addition ofthis composition to an oil-in-water emulsion enhances the cosmetic feelof the emulsion.

DETAIL OF THE DESCRIPTION OF EMBODIMENTS

Thus, according to a first aspect, the subject of the invention is theuse of an alkylpolyxyloside of formula:R—O—(X)_(p)  (I)in which:

-   p represents a decimal number between 1 and 5,-   X represents a xylose residue, and-   R represents a branched alkyl radical of formula:    CH(C_(n)H₂₊₁)(C_(m)H_(2m+1))—CH₂—    in which m is an integer between 6 and 12, n is an integer between 8    and 16 and the sum n+m is in the range from 14 to 26;

or alternatively of a composition consisting of a mixture of at leasttwo alkylpolyxylosides as defined above;

as agent enhancing the cosmetic feel of water-in-oil emulsionscontaining one or more polymers.

Preferably, the sum n+m is equal to 14, 16, 18, 22 or 26 and Rrepresents more particularly a 2-hexyldecyl (m=6, n=8), 2-octyldecyl(m=8, n=8), 2-hexyldodecyl (m=6, n=10), 2-octyldodecyl (m=8, n=10),2-decyltetradecyl (m=10, n=12) or 2-dodecylhexadecyl (m=12, n=14)radical. In a particularly preferred manner, the sum m+n is greater than16, and is advantageously equal to 18, 22 or 26, more preferably stillequal to 22 or 26.

In formula R-O—(X)_(p), the group R—O— is linked to X by the anomericcarbon of the xylose residue, so as to form an acetal functional group.

p, which represents the average degree of polymerization of the xylose,is more particularly between 1 and 2.5, and most particularly between 1and 2.0.

The compound of formula R—O—(X)_(p) may be prepared by reacting xylosewith an excess of a fatty alcohol of formula ROH, and then removing theunreacted fatty alcohol.

In the process as defined above, the reaction is carried out in thepresence of strong acid catalysts.

According to one variant of the process as defined above, the xylose isreacted with an alcohol of formula R₁—OH, in which R₁ contains from 1 to4 carbon atoms and more particularly with butanol, to give the acetal offormula R₁O—(X)_(p), which then undergoes transacetalization with anexcess of alcohol of formula ROH with distillation of the alcohol offormula R₁OH formed and then removal of the unreacted alcohol of formulaROH.

In this process and its variant, as described above, the removal of theunreacted alcohol of formula ROH is carried out according to methodsknown to persons skilled in the art such as for example distillation,thin-film distillation, molecular distillation or solvent extraction.

According to a second aspect, the subject of the present invention is anoil-in-water emulsion comprising:

-   -   from 0.1 to 15% by weight of one or more alkylpolyxylosides as        defined above;    -   from 0.05 to 10% by weight of one or more polymers;    -   more than 5% by weight, preferably more than 7% by weight, and        more preferably still more than 10% by weight, and up to 50% by        weight of a fatty phase consisting of one or more oils and/or        one or more waxes.

According to an advantageous embodiment, the alkylpolyxyloside offormula (I) is in the form of a mixture with its corresponding Guerbetalcohol (of formula ROH where R has the meaning given above), in analkylpolyxyloside/alcohol weight ratio in the range from 1/99 to 99/1.

Among the polymers used in the oil-in-water emulsion according to thepresent invention, there may be mentioned in particular homopolymers orcopolymers of acrylic acid, acrylic acid derivatives, acrylamide and itsderivatives, acrylamidomethylpropanesulfonic acid, vinyl monomer,trimethylaminoethylacrylate chloride such as for example the productsmarketed under the name CARBOPOL® Ultrez 10, PEMULEN® TR1 and TR2,SIMULGEL®A, SIMULGEL®NS, SIMULGEL®EPG, SIMULGEL®EG, LUVIGEL®EM,SALCARE®SC91, SALCARE®SC92, SALCARE®SC95, SALCARE®SC96, FLOCARE®ET100,HISPAGEL®, SEPIGEL®305, SEPIGEL®501, SEPIGEL®502, FLOCARE®ET58,STABILEZE®06; hydrocolloids of plant or biosynthetic origin such as forexample xanthan gum, karaya gum, carrageenans, alginates; silicates,cellulose and its derivatives; starch and its hydrophilic derivatives;polyurethanes.

Among the oils which can be used in the context of the presentinvention, there may be mentioned in particular:

-   -   oils of plant origin, such as sweet almond oil, copra oil,        castor oil, jojoba oil, olive oil, rapeseed oil, peanut oil,        sunflower oil, wheatgerm oil, corn germ oil, soybean oil,        cottonseed oil, alfalfa oil, poppy seed oil, pumpkinseed oil,        evening primrose oil, millet oil, barley oil, rye oil, safflower        oil, candlenut oil, passion flower oil, hazelnut oil, palm oil,        shea butter, apricot kernel oil, calophyllum oil, sisymbrium        oil, avocado oil, calendula oil;    -   vegetable oils and their ethoxylated methyl esters;    -   oils of animal origin, such as squalene, squalane;    -   mineral oils such as paraffin oil, liquid paraffin and        isoparaffins;    -   synthetic oils, in particular fatty acid esters such as butyl        myristate, propyl myristate, cetyl myristate, isopropyl        palmitate, butyl stearate, hexadecyl stearate, isopropyl        stearate, octyl stearate, isocetyl stearate, dodecyl oleate,        hexyl laurate, propylene glycol dicaprylate, esters derived from        lanolic acid, such as isopropyl lanolate, isocetyl lanolate,        monoglycerides, diglycerides and triglycerides of fatty acids,        such as glyceryl triheptanoate, alkyl benzoates,        poly-alpha-olefins, polyolefins such as polyisobutene, synthetic        isoalkanes such as isohexadecane, isododecane, perfluorinated        oils and silicone oils.

Among the waxes which can be used in the context of the presentinvention, there may be mentioned for example beeswax; carnauba wax;candelilla wax; ouricoury wax; Japan wax; cork fiber or sugarcane wax;paraffin waxes; lignite waxes; microcrystalline waxes; lanolin wax;ozokerite; polyethylene wax; hydrogenated oils; silicone waxes;vegetable waxes; fatty alcohols and fatty acids which are solid at roomtemperature; glycerides which are solid at room temperature.

The water-in-oil emulsion in accordance with the present invention mayalso optionally contain up to 15% by weight of an emulsifier.

Among the emulsifiers which can be used in the context of the presentinvention, there may be mentioned for example fatty acids; ethoxylatedfatty acids; fatty acid esters of sorbitol; ethoxylated fatty acidesters; polysorbates; polyglycerol esters; ethoxylated fatty alcohols;sucrose esters; alkylpolyglycosides; sulfated and phosphated fattyalcohols.

In a manner known per se, these emulsions may additionally comprise oneor more compounds chosen from humectants, such as for example glycerin,preservatives, colorants, perfumes, cosmetic active agents, inorganic ororganic sunscreens, inorganic fillers such as iron oxides, titaniumoxides and talc, synthetic fillers such as nylons and polymethylmethacrylates which are crosslinked or not, silicone elastomers,sericites and plant extracts.

The oil-in-water emulsions in accordance with the invention may beprepared in the following manner.

The aqueous phase is heated to a temperature of 70 to 85° C. Inparallel, the fatty phase containing the emusifying system of theinvention and the oils (optionally additivated with waxes, coemulsifiersand lipophilic active agents) is heated to an identical temperature of70 to 85° C. The two phases are then mixed and emulsified with the aidof a rotor-stator type emulsifier (for example a SILVERSON laboratorymixer). After a few minutes of emulsification, the emulsion is cooledwith gentle stirring. The polymer(s) are introduced into the oily phase,into the aqueous phase or directly into the emulsion according to therecommendations of the suppliers.

If all the components of the emulsion are liquid, the manufacture may becarried out without heating.

EXAMPLES

The invention will be illustrated with the following examples.

Example 1 Preparation of a 2-decyltetradecylxyloside

61.8 kg of 2-decyltetradecanol, marketed by the company SASOL under thename Isofol®24, are introduced into a reactor. 8.7 kg of xylose aregradually dispersed in the stirred medium and 65 g of sulfuric acid arethen added. The mixture is kept at 115° C. for 6 hours, under a partialvacuum, and then neutralized with caustic soda. After filtration, theclear liquid obtained has a hydroxyl value of 183 and contains 15% byweight of 2-decyltetradecylxyloside and 85% by weight of2-decyltetradecanol.

Example 2 Demonstration of the Feel Enhancement Obtained when theCompound According to Example 1 is Added to Cosmetic PreparationsContaining No Emulsifier

Two series of emulsions having the following compositions are prepared:

1st series Cetearyl octanoate 10% Water qsp 100% Polymer qsPreservatives qs 2nd series Compound according to example 1  3% Cetearyloctanoate 10% Water qsp 100% Polymer qs Preservatives qs

Mode of preparation: the polymer is dispersed in water and neutralizedif necessary, and then cetearyl octanoate is introduced into the gelformed. Homogenization of the emulsion is carried out without heating,by stirring with traditional items of equipment. The compound accordingto example 1 is added with cetearyl octanoate.

The preparations obtained are O/W emulsions.

A sensory evaluation is carried out on a panel of 20 trained volunteers.The results are presented in table 1. Each criterion is scored from 0 to5.

TABLE 1 Carbomer 0.4% Polyacrylamide and and acrylates/ C11-13steareth-20 Acryloyl isoparaffin methacrylate dimethyl and laureth-7:copolymer taurate Polymer 3% 0.2% copolymer 1% Evaluation of theemulsions without the compound according to example 1 Richness 2 0 0Residual film 2 1 1 Evaluation of the emulsions containing 3% of thecompound according to example 1 Richness 3 2 3 Residual film 4 3 3

The addition of 3% of the compound according to example 1 to thepolymer-based emulsions significantly enhances the richness andincreases the sensation of emollience, leaving a residual filmsignificantly perceived by the volunteers.

Example 3 Demonstration of the Feel Enhancement Obtained when theCompound According to Example 1 is Added to Cosmetic PreparationsContaining an Emulsifier

Two emulsions having the following composition are prepared:

Emulsifier   3%   3% Compound according to example 1   3% Cetearyloctanoate  10%  10% Water qs 100% qs 100% Polyacrylamide and C11-13 1.5%1.5% isoparaffin and laureth-7 Preservatives qs qs

The preparation of these emulsions is carried out according to aconventional process by emulsification in the hot state of 2 aqueous andoily phases.

The preparations obtained are O/W emulsions.

A sensory evaluation is carried out on a panel of 20 trained volunteers.The results are presented in table 2. Each criterion is scored from 0 to5.

TABLE 2 Arachidyl alcohol and behenyl PEG 100 alcohol and stearate andarachidyl glyceryl Ceteth 2 + ceteth Emulsifier glucoside stearate 21Evaluation of the trials without the compound according to example 1Richness 1 1 0 Residual film 1 1 1 Evaluation of the trials containing3% of the compound according to example 1 Richness 3 2 2 Residual film 33 3

The addition of 3% of the compound according to example 1 makes itpossible to significantly enhance the sensory profile of the emulsionstested by simultaneously increasing the richness and the residual film.

It will be understood that many additional changes in the details,materials, steps and arrangement of parts, which have been hereindescribed in order to explain the nature of the invention, may be madeby those skilled in the art within the principle and scope of theinvention as expressed in the appended claims. Thus, the presentinvention is not intended to be limited to the specific embodiments inthe examples given above.

1. A composition to enhance the cosmetic feel of oil-in-water emulsionscomprising: a fatty phase; and at least one alkylpolyxyloside, wherein,said composition is free of an aqueous phase, and said alkylpolyxylosideis represented by formula (I):R—O—(X)_(p)  (I), wherein said p is the average degree ofpolymerization, and is a decimal number between 1 and 5, wherein said Xis a xylose residue, and wherein said R is a branched alkyl radicalrepresented by the formula:CH(C_(n)H_(2n+1))(C_(m)H_(2m+1))CH₂—; wherein said m is an integer inthe range of from 6 to 12, wherein said n is an integer in the range offrom 8 to 16, and wherein the sum m+n is in the range of from 14 to 26.2. The composition according to claim 1, wherein said p is between 1 and2.5.
 3. The composition according to claim 2, wherein p is between 1 and2.0.
 4. The composition according to claim 1, wherein the sum m+n isequal to at least one integer selected from the group consisting of: a)14, b) 16, c) 18, d) 22, and e)
 26. 5. The composition according toclaim 4, wherein said sum is greater than
 16. 6. The compositionaccording to claim 4, wherein said sum is equal to
 18. 7. Thecomposition according to claim 4, wherein said sum is equal to
 22. 8.The composition according to claim 4, wherein said sum is equal to 26.9. The composition according to claim 1, wherein said R is at least onecomponent selected from the group consisting of: a) 2-hexyldecyl, b)2-octyldecyl, c) 2-hexyldodecyl, d) 2-octyldodecyl, e)2-decyltetradecyl, and f) 2-dodecylhexadecyl radical.
 10. Anoil-in-water emulsion composition comprising: an aqueous phase; morethan 5% by weight of a fatty phase; and from 0.1 to 15% by weight of atleast one alkylpolyxyloside represented by formula (I)R—O—(X)_(p) (I), wherein said p is a decimal number between 1 and 5,wherein said X is a xylose residue, and wherein said R is a branchedalkyl radical represented by formula (II):CH(C_(n)H_(2n+1))(C_(m)H_(2m+1))—CH₂— wherein said m is an integer inthe range of from 6 to 12, wherein said n is an integer in the range offrom 8 to 16, and wherein the sum of n+m is in the range of from 14 to26.
 11. The composition according to claim 10, wherein said fatty phaseis up to 50% by weight of said composition.
 12. The compositionaccording to claim 11, wherein said fatty phase comprises at least onecomponent selected from the group consisting of: a) oils; and b) waxes.13. The composition according to claim 12, wherein said oil is selectedfrom the group consisting of: a) oils of plant origin, b) sweet almondoil, c) copra oil, d) castor oil, e) jojoba oil, f) olive oil, g)rapeseed oil, h) peanut oil, i) sunflower oil, j) wheatgerm oil, k) corngerm oil, l) soybean oil, m) cottonseed oil, n) alfalfa oil, o) poppyseed oil, p) pumpkinseed oil, q) evening primrose oil, r) millet oil, s)barley oil, t) rye oil, u) safflower oil, v) candlenut oil, w) passionflower oil, x) hazelnut oil, y) palm oil, z) shea butter, aa) apricotkernel oil, bb) calophyllum oil, cc) sisymbrium oil, dd) avocado oil,ee) calendula oil; ff) vegetable oils and their ethoxylated methylesters, gg) oils of animal origin, such as squalene, hh) mineral oils,ii) paraffin oil, jj) liquid paraffin, kk) isoparaffins; ll) syntheticoils, mm) fatty acid esters, nn) butyl myristate, oo) propyl myristate,pp) cetyl myristate, qq) isopropyl palmitate, rr) butyl stearate, ss)hexadecyl stearate, tt) isopropyl stearate, uu) octyl stearate, vv)isocetyl stearate, ww) dodecyl oleate, xx) hexyl laurate, yy) propyleneglycol dicaprylate, zz) esters derived from lanolic acid, aaa) isopropyllanolate, bbb) isocetyl lanolate, ccc) monoglycerides, ddd)diglycerides, eee) triglycerides of fatty acids, fff) glyceryltriheptanoate, ggg) alkyl benzoates, hhh) poly-alpha-olefins, iii)polyolefins, jjj) polyisobutene, kkk) synthetic isoalkanes, lll)isohexadecane, mmm) isododecane, nnn) perfluorinated oils, and ooo)silicone oils.


14. The composition according to claim 12, wherein said wax comprises atleast one component selected from the group consisting of: a) beeswax,b) carnauba wax, c) candelilla wax, d) ouricoury wax, e) Japan wax, f)cork fiber, g) sugarcane wax, h) paraffin waxes, i) lignite waxes, m)microcrystalline waxes, n) lanolin wax, o) ozokerite, p) polyethylenewax, q) hydrogenated oils, r) silicone waxes, s) vegetable waxes, t)fatty alcohols, u) fatty acids, and v) glycerides.


15. The composition according to claim 10, wherein saidalkylpolyxyloside is in the form of a mixture with its correspondingalcohol of formula ROH.
 16. The composition according to claim 15,wherein the weight ratio of alkylpolyxyloside/alcohol is in the range offrom 1/99 to 99/1.
 17. The composition according to claim 10, whereinthe sum of m+n is equal at least one integer selected from the groupconsisting of: a) 14, b) 16, c) 18, d) 22, and e)
 26. 18. Thecomposition according to claim 17, wherein said integer is greater than16.
 19. The composition according to claim 17, wherein said integer isgreater than or equal to
 22. 20. The composition according to claim 17,wherein said integer is greater than or equal to
 26. 21. The compositionaccording to claim 10, wherein said R is at least one component selectedfrom the group consisting of: a) 2-hexyldecyl, b) 2-octyldecyl, c)2-hexyldodecyl, d) 2-octyldodecyl, e) 2-decyltetradecyl, and f)2-dodecylhexadecyl.